1. Field of the Invention
The present invention relates to filling and sealing openings in a laminate and in particular to an apparatus and method for sealing the electrical connection area of an antenna formed between the two glass plies of a laminated transparency.
2. Technical Considerations
In the past, the traditional motor vehicle antenna for receiving and transmitting electromagnetic signals was a mast or whip-type antenna. Recently there has been a trend towards incorporating the antenna into the vehicle structure. For example, U.S. Pat. No. 3,987,449 to DeAngelis et al. discloses a wire antenna laminated within a vehicle windshield. U.S. Pat. No. 4,707,700 to Nagy positions an antenna within the roof structure of a vehicle. U.S. Pat. No. 5,416,491 to Nishikawa et al. forms antenna elements on a window using electroconductive ceramic paints. U.S. Pat. Nos. 4,768,037 and 4,849,766 to Inaba et al. and 5,355,144 to Walton et al. use a transparent electroconductive coating laminated between two glass plies to form an antenna. U.S. Pat. No. 5,083,1 35 to Nagy et al. utilizes a transparent coating in the form of a "T" to form an antenna. In each system, the connector arrangement conducts the signals received by the antenna to a receiver, for example a radio.
In order to feed the signals received by the antenna element to a signal receiving device, connectors, such as wires, braids or metal tabs, have been used. When the antenna is formed from electroconductive elements laminated with a transparency, e.g. a windshield, problems arise when these connector elements are also laminated within the transparency. In particular, it has been found that when incorporating these types of connectors between the plies of the glass laminate, air may be entrapped within the laminate in the vicinity of the connector. It is believed that the connector hinders de-airing of the laminate during a conventional roll prepress operation. The bubbles formed by the entrapped air detract from the aesthetics of the window as well as increase the possibility of delamination at or near the connector. To avoid this problem, a notch may be cut along the edge of one of the glass plies to facilitate electrical connection to antenna elements that extend within the notch area, e.g. as disclosed in U.S. Pat. Nos. 3,987,449 and 4,849,766. A similar approach is disclosed in U.S. Pat. No. 5,213,828 to Winter et al. where electrical connection was required to be made to electroconductive elements of an electrically heatable windshield. To protect the connection and seal the notch area, the notch area is filled with a sealant material which is typically applied to the notch area and smoothed with a putty knife or other similar tool. As an alternative, tape may be used to cover the notch area and the sealant is injected into the notch beneath the tape. These sealing procedures are slow and do not provide consistent, reliable results. In particular, it is difficult to ensure that the notch area is completely filled. In addition, the exposed surfaces of the sealant material along the major surface of the windshield and along its edge may be irregular. This may pose a problem when adhesive is applied about the marginal edge of the windshield before it is mounted in a vehicle.
It would be advantageous to provide an arrangement where the notch area is effectively filled quickly and consistently, and further provides a smooth finish along the sealant surface.